xfs: better xfs_trans_alloc interface

Merge xfs_trans_reserve and xfs_trans_alloc into a single function call
that returns a transaction with all the required log and block reservations,
and which allows passing transaction flags directly to avoid the cumbersome
_xfs_trans_alloc interface.

While we're at it we also get rid of the transaction type argument that has
been superflous since we stopped supporting the non-CIL logging mode.  The
guts of it will be removed in another patch.

[dchinner: fixed transaction leak in error path in xfs_setattr_nonsize]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index e7c49cf..9a462e8 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -90,7 +90,6 @@
  */
 typedef struct xfs_trans {
 	unsigned int		t_magic;	/* magic number */
-	unsigned int		t_type;		/* transaction type */
 	unsigned int		t_log_res;	/* amt of log space resvd */
 	unsigned int		t_log_count;	/* count for perm log res */
 	unsigned int		t_blk_res;	/* # of blocks resvd */
@@ -148,10 +147,9 @@
 /*
  * XFS transaction mechanism exported interfaces.
  */
-xfs_trans_t	*xfs_trans_alloc(struct xfs_mount *, uint);
-xfs_trans_t	*_xfs_trans_alloc(struct xfs_mount *, uint, xfs_km_flags_t);
-int		xfs_trans_reserve(struct xfs_trans *, struct xfs_trans_res *,
-				  uint, uint);
+int		xfs_trans_alloc(struct xfs_mount *mp, struct xfs_trans_res *resp,
+			uint blocks, uint rtextents, uint flags,
+			struct xfs_trans **tpp);
 void		xfs_trans_mod_sb(xfs_trans_t *, uint, int64_t);
 
 struct xfs_buf	*xfs_trans_get_buf_map(struct xfs_trans *tp,